This invention relates to new and useful improvements in load shifting assemblies normally used with heavy duty trailers and examples of such devices include U.S. Pat. Nos. 4,161,325, 3,700,255, 2,772,892 and 2,741,409.
U.S. Pat. No. 4,161,325 shows a supplementary support for vehicles for the reduction of load which comprises lever arms, a cam member, a cam roller and associated components. U.S. Pat. No. 3,700,255 discloses a pivotal axle which prevents scuffing of tires during the turning operation, by yielding to a normal course with respect to the direction of trarms, a cam member, a cam roller and associated components. U.S. Pat. No. 3,700,255 discloses a pivotal axle which prevents scuffing of tires during the turning operation, by yielding to a normal course with respect to the direction of travel and the other two patents disclose load distributing vehicles or trailers.
As taught by these patents, the main function of a load shifting device is to relieve the running gear of the trailer, of a certain amount of imposed payload so that larger payloads can be legally be hauled on highways, the majority of which are subjected to weight limitations per axle or per wheel.
In order to be effective and to reduce the drag on the tires and also to decrease the turning radius, a load shifter must have self-steering capabilities and although there are several different designs of self-steering gears available for load shifters, most of them suffer from certain disadvantages such as involved construction, many wear areas particularly when used in dusty or dirty conditions and somewhat inefficient self-centering actions.